initrd: use do_mount() instead of ksys_mount()

All three calls to ksys_mount() in initrd-related kernel code can
be switched over to do_mount():
- the first and third arguments are const strings in the kernel,
  and do not need to be copied over from userspace;
- the fifth argument is NULL, and therefore no page needs to be,
  copied over from userspace;
- the second and fourth argument are passed through anyway.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

diff --git a/init/do_mounts_initrd.c b/init/do_mounts_initrd.c
index a9c6cc56f505e6210356b0c8d94e8aa90dbc2aa7..3bf7b74153ab7b04635253fb8d64c4eaf08f9d12 100644 (file)
--- a/init/do_mounts_initrd.c
+++ b/init/do_mounts_initrd.c
@@ -54,7 +54,7 @@ static int init_linuxrc(struct subprocess_info *info, struct cred *new)
        ksys_dup(0);
        /* move initrd over / and chdir/chroot in initrd root */
        ksys_chdir("/root");
-       ksys_mount(".", "/", NULL, MS_MOVE, NULL);
+       do_mount(".", "/", NULL, MS_MOVE, NULL);
        ksys_chroot(".");
        ksys_setsid();
        return 0;
@@ -89,7 +89,7 @@ static void __init handle_initrd(void)
        current->flags &= ~PF_FREEZER_SKIP;
 
        /* move initrd to rootfs' /old */
-       ksys_mount("..", ".", NULL, MS_MOVE, NULL);
+       do_mount("..", ".", NULL, MS_MOVE, NULL);
        /* switch root and cwd back to / of rootfs */
        ksys_chroot("..");
 
@@ -103,7 +103,7 @@ static void __init handle_initrd(void)
        mount_root();
 
        printk(KERN_NOTICE "Trying to move old root to /initrd ... ");
-       error = ksys_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL);
+       error = do_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL);
        if (!error)
                printk("okay\n");
        else {